/*
* return num random images from the set
*/
function random_images(num) {
	var images = [
	'images/vignettes/chloe_swing.jpg',
	'images/vignettes/dillon_breathing.jpg',
	'images/vignettes/kate_crow.jpg',
	'images/vignettes/ldog.jpg',
	'images/vignettes/madison_rainbow.jpg'
	]

	if (num < 1 || num > images.length) return;

	var i, j=images.length - num;
	for (i=0; i<j; i++) {
		var k = parseInt(Math.random() * images.length);
		images.splice(k, 1);
	}
	images.sort(function() { return 0.5 - Math.random() });
	return images;
}